implementation of message threadings.

[ymnk jcraft com (Atsuhiko Yamanaka)]

Hi there,

This mail is attached a patch file to balsa-1.0.pre5,
which includes message threading functions and
some hacks for improving the performance of balsa.

I wrote two message threading functions and they are
included src/balsa-index-threading.c 

And I had to do some hacks for improving the performance of balsa,
because the message threading functionality heavily depends  on the
GtkCTree widget and it is not so lightweight in comparison with the GtkCList.
Try following operations on balsa-1.0.pre5 and patched balsa-1.0.pre5.
  * select hundreds messages and transfer to other mailbox.
  * open a mailbox, which includes hundreds messages and exit(type C-q).
If you use balsa on the remote host, you will find improvements clearly.

--
ymnk, JCraft Inc., mailto: ymnk@jcraft.com

balsa-1.0.pre5.threading.diff